/*
 * FindBugs - Find Bugs in Java programs
 * Copyright (C) 2003-2008, University of Maryland
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

package edu.umd.cs.findbugs.ba.jsr305;

import edu.umd.cs.findbugs.SystemProperties;
import edu.umd.cs.findbugs.classfile.MethodDescriptor;
import edu.umd.cs.findbugs.util.DualKeyHashMap;
import java.util.HashMap;
import java.util.Map;

/**
 * Store computed type qualifiers for method parameters
 * and return values.  This allows interprocedural checking
 * of type qualifiers.
 * 
 * @author David Hovemeyer
 */
public class TypeQualifierDatabase {
	/**
	 * If true, populate and use interprocedural database.
	 */
	public static final boolean USE_DATABASE = SystemProperties.getBoolean("ctq.usedatabase", true);
	
	public static final boolean DEBUG = SystemProperties.getBoolean("ctq.db.debug");
	
	private Map<MethodDescriptor, Map<TypeQualifierValue, TypeQualifierAnnotation>> returnValueMap;
	private DualKeyHashMap<MethodDescriptor, Integer, Map<TypeQualifierValue, TypeQualifierAnnotation>> parameterMap;
	
	/**
	 * Constructor.
	 */
	public TypeQualifierDatabase() {
		this.returnValueMap = new HashMap<MethodDescriptor, Map<TypeQualifierValue, TypeQualifierAnnotation>>();
		this.parameterMap = new DualKeyHashMap<MethodDescriptor, Integer, Map<TypeQualifierValue, TypeQualifierAnnotation>>();
	}
	
	/**
	 * Set a TypeQualifierAnnotation on a method return value.
	 * 
	 * @param methodDesc the method
	 * @param tqv        the type qualifier
	 * @param tqa        the type qualifier annotation
	 */
	public void setReturnValue(MethodDescriptor methodDesc, TypeQualifierValue tqv, TypeQualifierAnnotation tqa) {
		Map<TypeQualifierValue, TypeQualifierAnnotation> map = returnValueMap.get(methodDesc);
		if (map == null) {
			map = new HashMap<TypeQualifierValue, TypeQualifierAnnotation>();
			returnValueMap.put(methodDesc, map);
		}
		map.put(tqv, tqa);
		
		if(DEBUG) {
			System.out.println("tqdb: " + methodDesc + " for " + tqv + " ==> " + tqa);
		}
	}
	
	/**
	 * Get the TypeQualifierAnnotation on a method return value.
	 * 
	 * @param methodDesc the method
	 * @param tqv        the type qualifier
	 * @return           the type qualifier annotation on the method return value,
	 *                   or null if no (interesting) type qualifier annotation
	 *                   was computed for this method
	 */
	public TypeQualifierAnnotation getReturnValue(MethodDescriptor methodDesc, TypeQualifierValue tqv) {
		//
		// TODO: handling of overridden methods?
		//
		Map<TypeQualifierValue, TypeQualifierAnnotation> map = returnValueMap.get(methodDesc);
		if (map == null) {
			return null;
		}
		return map.get(tqv);
	}
	
	/**
	 * Set a TypeQualifierAnnotation on a method parameter.
	 * 
	 * @param methodDesc the method
	 * @param param      the parameter (0 == first parameter)
	 * @param tqv        the type qualifier
	 * @param tqa        the type qualifier annotation
	 */
	public void setParameter(MethodDescriptor methodDesc, int param, TypeQualifierValue tqv, TypeQualifierAnnotation tqa) {
		Map<TypeQualifierValue, TypeQualifierAnnotation> map = parameterMap.get(methodDesc, param);
		if (map == null) {
			map = new HashMap<TypeQualifierValue, TypeQualifierAnnotation>();
			parameterMap.put(methodDesc, param, map);
		}
		map.put(tqv, tqa);

		if(DEBUG) {
			System.out.println("tqdb: " + methodDesc + " parameter " + param +  " for " + tqv + " ==> " + tqa);
		}
	}
	
	/**
	 * Get the TypeQualifierAnnotation on a parameter.
	 * 
	 * @param methodDesc the method
	 * @param param      the parameter (0 == first parameter)
	 * @param tqv        the type qualifier
	 * @return           the type qualifier annotation on the method return value,
	 *                   or null if no (interesting) type qualifier annotation
	 *                   was computed for this method
	 */
	public TypeQualifierAnnotation getParameter(MethodDescriptor methodDesc, int param, TypeQualifierValue tqv) {
		//
		// TODO: handling of overridden methods?
		//
		Map<TypeQualifierValue, TypeQualifierAnnotation> map = parameterMap.get(methodDesc, param);
		if (map == null) {
			return null;
		}
		return map.get(tqv);
	}
}
